Machine-gun casing



E. FOWLER.

MACHINE GUN CASING.

lPPLxcATlou flu-:D uEc.4. ma.

1,434,812, .mallteam 7,1922.

Patented Nov. 7, 1922.

ELBEET POWER, OF THE UNITED STATES AY.

MACHINE-GUN CASING.

Application filed December 1918. serial No. 265,240.

To all/whom it may concern:

Be it known that I, ELBERT FowLER, captain, Ordnance Department, United States Army, a citizen of the United States, stationed at Washington, District of Columbia, have invented an improvement in Machine- Gun Casings, of which the following is a specificatie The object of my invention is to provide a machine gun in which the breech casin and water jacket are axially aligned and in one integral piece.

As machine guns have heretofore been constructed, the breech casing and the water jacket have been two separate members suitably connected as by a screw threaded connection (as in the well known Brownin gun), and the water jacket has been o set with relation to the breech casing, so that the barrel of the gun lies below the longitudinal center of the water jacket and adjacent the bottom thereof, for a purpose well known to those acquainted with machine guns, namely, to keep the barrel covered with a cooling medium when the gun is tilted. Experience has shown that a machine gun comprising a water jacket and a breech casing united by a threaded joint presents disadvantages, because the gun sometimes breaks at the joint and, even if no break occurs, the shock and vibration of the gun in use-tend to strip the threads, causing leakage at the joint.

Another object is to provide a n ovel arrangement of the barrel with relation to the' Water jacket, whereby, notwithstanding the fact that the breech casing and cooling jacket are in axial alinement, and not offset, as in other constructions, no portion of the barrel exposed to the cooling medium when the gun is in a horizontal plane will be exposed by said medium when the gunis tilted, so as to incline upward.

Another object is to provide novel means for securing and locking the rear end plate of the gun.

Another object is to provide a locking means, common to both the end plate and cove-r of the gun, for locking both or for selectively unlocking either.

Another object is to provide a novel means for permitting inlet of water to the water jacket.

Another object is to provide a novel construction of support for the bearing of the my invention. '65

Fig. 2 is a central longitudinal sectional view thereof.

Fig. 3 is a detached detail view, in rear elevation, of the rear end plate or handleblock.

Figs. 4 and 5 are sectional views on the lines 4 4 and 5-5 respectively, Fig. 1.

Referring now in detail to the drawing: As shown, the water-jacket 1 andthe breech casing 2 are integral and coaxial, 7a

and are formed of a singlepiece of tubin The water jacket 1 at its forward end 1s internally threaded, as shown at 3, for engagement with the threaded end of the cap e provided with a tubular, re-entrant bear- 8o ing 5, through which slides the barrel 6, the bushing 7 being screwed into the end of the' bearing 5 around the barrel 6, to provide a water tight joint.

The water jacket, towards its rear end, is provided with a thickened portion 8., pro- Y vided with screw threads 9, for engagement with the exterior screwthreads of the member 10. 'The barrel 6 is slidably mounted in the tubular, upwardly and rearwardly inclined bearing 11, which Vforms a part of the member 10.

It will be noted in the construction described, that the barrel 6 is disposed in a f position which is inclined to the axis of the water jacket 1, the barrel inclining forwardly toward the bottom of the water jacket, so that, when the barrel is tilted upward, the water level is still over the barrel. l

The water jacket 1 is provided with a threaded circular aperture 12 in which is threaded a cup-shaped valve-casing 13, having` an annular flange 14 for engaging the outer surface of the water jacket, and an 105 internal valve seat 15, against which is nor-v mally seated a disk-valve 16, having a stem 17 slidable in a bearing 18 in the bottom of the cup-shaped casing 13.

Between 'the valve 16 and :the bottom of the casing is dispos/ed a coiled spring 19,

. valve 16 is opened. The rear end plate or handle block 21 is bowed, as shown, for the purpose of increased strenglth, and is'provided with a flange 22, aving exterior parallel ribs extending partially around the circumference thereof and engageable with corresponding grooves in the rear'end of the breech casing 2. As shown, in this instance, there are two diametrically-oppositely disposed pairs of ribs on the flange 22 and two diametrically opposite pairs of 4grooves in the breech casing 2. The handle block lor plate-21 is assembled with the breech casing by sliding it into the end of the latter until one end of the ribs registers with the corresponding end of the grooves; then by a partial turn of the handle block therr ribs enter the grooves, so that the handleblock is held against longitudinal removal.

To secure the handle-block against acci-` dental withdrawal by rotation thereof, due to shock and vibration, suitable mechanism may be provided. In this instance, I have shown the end plate 2-1 as provided with twolugs 23, between which is adapted to protecta slidable latch 24, provided with an operating-stem 25, projecting through a longitudinally extending slot 26, in the breech casing 2, and provided, at its'exterior end, with a-handle 27.l l Y j lAs shown in Figure 2,'the latch is common to both the handle block 21 and the hinged cover 28 of the breech casing', and is operable to lock both or selectively to unlock either the cover 28 or the cover and handle blocks 21.

The forward end of the slidable latch is engageable with a recess in the lug 29 carried b the cover 28 on the end surface thereo y Referring especially tov Fig. 2 of the drawing, it is evident that there is suicient clearance between the rear end of the latch bar 24 and the flange 22 to permit the latch bar to be slidv rearwardly a suiicient 'distance to disen -age the forward end from j the recess in t e lug 29 of the cover'plate 28. When the latch bar is so moved rearwardly the cover late is unlatched and may gly so that the latch bar may then be forced forwardly to disengage the rear end from between thev lugs 23, which will free thehandle block and allowthe same to' be rotated and removed.

Carried by the rear end of the water jacket. is a split cover or ring 30 having internal, circumferential, marginal flanges 31. v The ring is provided adjacent the split 32 with apertured ears 33, 33. Through the aper.

tures of the ears 33,v 33 passes a tubular bearin 34. 1n assembling the rin 30 and the tu ular member 34, in manu acturing the gun, the ring 30l is slipped onto the water jacket 1 and moved to the position thereof shown in Figs. 1 and 2. The ears 33 are then placed in a vise, and the vise jaws closed to move the ears toward each other,v thus contracting the ring or collar 30 tightly around the water jackety 1. The tubular member 34, previously heated to a malleable condition, is then slipped through the apertures in the ears 33, 33 while hot. The tubular member 34 isprovided with a circumferential ange or upset end 35, the other projecting end of the tube 34 being plain. A swagin tool is then used to upset said other projectlng end ofthe tube against the ear 33, as shown in Fig. 5, at 36. This swagin or upsetting is done while the metallic tu e 34 .is still hot and malleable. As the tube 34. cools, it contracts, binding the collar 30 more tightly against the water jacket 1.. lThe collar 30 is thus, as it were, shrunk upon the water jacket 1.

From the above detailed description and 'arrangement `of the different parts, the

mlany advantages of my invention will be apparent, especially to those skilled in the art to which the invention pertains. Among such advantages may be mentioned the followin t 1. llgrom the construction of the water jacket and breech casing in one piece the following beneficial results are obtained:

. (a) A considerable saving in time. in the manufacture of the gun, y(b) .the water jacket and the breech casing are stronger" than when made in two pieces (as above pointed out), (c)-there is no dangerof leakage of the water because there is no joint between the -Iwater jacket and the breech casing.

2. The arrangement `of the barrel at an incline with respect tothe axis of the water jacket permits a coaxial relationship of the water jacket and the breech casing, and avoids the necessity of offsetting the water jacket with relationto the breech casing, that is, of disposing the water jacket and the breech casing in non-concentricA relationship. The barrel being inclined with respect tothe water chamber permits the gun to be tilted upward, thus maintaining the -level of the water above the barrel at all points thereof within the water jacket.

3. The provision of the lookin latch common to both the breech cover an the handle block obviates the expense of separate latches for these parts, and the additional labor of assembling two parts. j

4. The construction of the collar 3Q and the method of assemlblingh .therewith the tubular bearingv 34 insure a rm and immovable seating of said bushing on the Water jacket. f-

with a breech casin having a movable i cover, of a rear end p ate rotatable engageable with said breech casing, and a slidable latch common to both said cover and said plate for locking the cover and for also locking the plate against accidental rotation.

In testimony whereof I aix my signature.

- ELBERT FOWLER 

